How to make your own rain catchment system

Making the most of our most natural resource

Water flowing into rain barrel

Rain collection or “catchment” systems come in a wide variety of shapes and sizes. Choose the container and system best suited to your particular needs.

Every drop of water is precious. But it’s not always available. In some areas, drought and growing populations are stressing water supplies. Several cities across the country even offer tax incentives for installing rain collection, or rain catchment, systems. All of this is making this age-old technology more popular with today’s homeowners. While some people want to collect rainwater for all of their household purposes, we’re focusing here on water for irrigation and landscaping needs.

It’s been estimated that for every inch of rain that falls, a 1,000-square-foot roof can collect 600 gallons of water. While some catchment systems are quite elaborate, collecting rain water can be as simple as positioning a barrel at the end of a downspout.

Rain catchment system materials

  • Gutters with wire-mesh screens. The screens will help keep out leaves and other debris.
  • A storage barrel or tank. Choose something that’s easy to clean. Most hardware stores, as well as lawn and garden supply stores, sell 55- to 75-gallon plastic rain barrels, equipped with screens and spouts. Receptacles can also be made of cement, metal, wood, fiberglass or stone. You’ll also want a cover to prevent mosquitos from breeding in the standing water. Shading the tank from sunlight will help to avoid algae growth.
  • A way for the water to move out of the tank. The two most common methods are gravity and pumps. Gravity is obviously the least expensive. Just open the valve or spigot located at the bottom of the tank. Pumps mounted near the tanks can speed the emptying process.
Rain Barrel

A basic catchment system taps into your downspout and relies on gravity to distribute the water. More elaborate systems can involve filtration and pumps.

If you plan to irrigate vegetable or fruit gardens, do some additional research on creating a potable water catchment system. You’ll want to take extra precautions to ensure that your roof and collection system are non-toxic. Galvanized gutters and tanks, for example, can release zinc into the water. You’ll also want to protect collected water from bird droppings. And your storage receptacle should be made of a material that is easy to clean. While fiberglass may not be the most decorative, it is durable and one of the simplest materials to maintain.

What’s old is new again. Rain catchment supplies vary from simple to complex. Be sure to match your needs (lawn watering vs. potable water) to the right system to ensure you have the proper amount of filtration required for both plants and people. This is yet another way to “live in Harmony” while improving your outdoor living environment.